As an increasing number of vehicles enter into ordinary families, there are more and more vehicles driving on roads. Accordingly, installed with more on-board equipment such as on-board air conditioner, on-board stereo and vehicle window systems, etc., the vehicles become increasingly intelligent and user-friendly. However, the control panel of on-board equipment is usually disposed in the front of the vehicle and therefore accessible only by occupants seated at front row seats. Accordingly, occupants seated on back row seats have to rely on front row occupants to operate the equipment, greatly degrading their riding experience. On the other hand, requirements for controlling these equipment vary from occupant to occupant according to their specific on-board positions, so the first thing to do is to determine each occupant's specific position so as to meet their operating requirement. This problem is what the application aims to solve.